Republican White House hopeful Marco Rubio says that anger alone isn't enough to qualify someone to be president.The Florida senator is taking a swipe at his party's front-runners during a campaign stop in Johnston, Iowa, on Saturday. He says that leading GOP candidate Donald Trump in particular doesn't offer details about his plans for critical issues like foreign policy.Rubio is calling out Trump and Texas Sen. Ted Cruz by name during the town hall-style meeting, the first of four scheduled campaign appearances to court Iowa voters ahead of the state's Feb. 1 caucuses.Trump and Cruz are surging in the polls, in part, because they've successfully tapped into conservative anger about the direction of the country.

The Florida senator is taking a swipe at his party's front-runners during a campaign stop in Johnston, Iowa, on Saturday. He says that leading GOP candidate Donald Trump in particular doesn't offer details about his plans for critical issues like foreign policy.

Rubio is calling out Trump and Texas Sen. Ted Cruz by name during the town hall-style meeting, the first of four scheduled campaign appearances to court Iowa voters ahead of the state's Feb. 1 caucuses.

Trump and Cruz are surging in the polls, in part, because they've successfully tapped into conservative anger about the direction of the country.